Exploration for Uranium in the Athabasca Basin

Abstract

The Athabasca sandstone was deposited about 1450 million years ago in a depression floored by deeply weathered gneisses. The bottom of the sandstone acted as an aquifer for oxidizing groundwater; trace amounts of uranium in solution were deposited where a reducing environment was encountered. The concept or model on which much exploration has been based is that fault zones, cutting graphitic metasediments in the basement and extending up into the sandstone, were preferred sites for uranium deposition.

Exploration considerations include assessment of the relative potential for uranium of different parts of the Athabasca basin, rating the different types of anomalies for their geological significance, and evaluating geophysical methods which are most likely to provide meaningful results. Recognition, in drill core, of alteration associated with mineralization will permit more efficient spacing of drill holes.